Boat



Aug.' 7, 19.45- c. c. sHEr-PARD BOAT v 3 Sheets-Sheet 1 Original FiledSept. 19, 1941 Augf?, 1945. c. c. sHEPPARD 2,381,622

'Y BOAT original Filed Sept. 19, 1941 s sheets-sheet 2 .l By c'. c'..swig/Afa Aug# 7 1945 c. c. SHEPPARD 2,38L5622 BOAT Original Filed Sept.19, 1941 3 Sheets-Sheet 3 ,y

K INVENTQR.

c. a s//fPPA /w www Patented ug. 7, 1945 i i UNITEDJSTATES PATENToFF-'ICE Creedy Sheppard, Fort Lee, N. J.

substituted for yabandoned` application Serial No.`

411,578, September 19, 1941. `This application v p October 17, 1944,Serial No."559,026

6 Claims. (Cl. 1154-37) This application is a substitute for applicationSer. No. 411,578, iiled September 19, 1941, for Boats, and the inventionrelates more particularly to thattype including speed boats and seasleds, it being one object ofthe invention to provide a `boat of suchconstruction that high speed or propulsion is obtained. While it hasbeen stated that .the improved construction is particularly adapted forspeed boats and sea sleds, it is to be understood that it is not limitedto thisI particular type of boat. f

Another object ol` the invention is to provide a boat having its hull soconstructed that it includes runners` extending longitudinally thereofat opposite sides oi its bottom and constituting streamlined shields forpropellers housed therein and having portions protruding downwardlythrough openings formed intermediate the length of the runners. .l

Another object of the invention is to provide a lboat wherein `an airpocket is formed under the bottomof the boat between the runners toreduce friction between the water and bottom of the boat and thus aid inincreasing the speed of theboat. l i

Another object of the invention is to provide the bottom of the boatwith cross bars or strips extending transversely thereof between frontand rear ends of the yrunners and constituting iront and rear walls ofthe air pocket, the strips being of appreciably less depth than therunners and so formed in cross section that the `boat may moverapidlythrough the water and air pass out from the pocket at the stern ofA theboat as it moves forwardly.

Another object of the invention'is to provide a boat wherein engineexhaust is discharged into an air pocket under the hull for effectingincreased buoyancy and, 1n the case-of airplane pontoons, to increasethe buoyancy and turbulence and decrease surface tensionV on take-off.

Another object of the invention is to so construct the boat` that as itsspeed is increased, air and exhaustgases moving rearwardly in the airpocket will have a tendency to shift the boat upwardly and thus reduceits draft and, consequently, reduce frictional drag of the water uponthe bottom of the boat.

Another object-l of the invention is to provide the boat with runners soformed that they taper y rearwardly and thus impart a streamlined effectto the runners and also cause the pocket to gradually increase in widthtoward its rear end.`

mize frictional thrust and turbulence as the boat is driven through thewater and thus permit the boat to be propelled forwardly atincreasedspeed with an engine of predetermined horsepower.y

Another object of the invention is to produce Another object of theinvention is to minir a boat simple in construction, neat and attractivein appearance, and very sturdy.

In the accompanying drawings: 1

Fig. l is a top plan view of a boat of the improved construction.

Fig. 2 is a view showing the boat in side elevation with one of thepontoons or runners shown in longitudinal section.

Fig. 3 is a view looking at the bottom of the boat.

Fig. 4 is a sectional View taken longitudinally through the boat, on theline 4-4 of Fig. 1.

Fig. 5 is'a sectional view taken transversely through the boat on theline 5-5 of Fig. 2.

Fig.` 6 is a `fragmentary sectional view taken transversely through thebottom of the boaty on the lineV 6-6 of Fig. 2.

Fig. 'l is a transverse sectional view showing the normal draft of theboat. Fig. 8 is a similar view showing the draft of the boat when inmotion.

The boat l may be of any length and beam desired and has a bottom 2which is at for the full width of the hull and also flat forapproximately its entire length, the portion 3 of the bottom beingcurved upwardly so that, as the boat is propelled forwardly, water willflow easilylunder the bow thereof. Pontoons or runners 4 extendlongitudinally of the boat along opposite sides of the bottom 2 and,from an inspection of Figs. 3 and 4, it will be seen that these pontoonsor runners taper transversely toward their rear ends and also decreasein depth rearwardly. The runners are V-shaped in .cross section, asshown in Figs. 5 through 8, and are hollow, each being closed at itsends and having its forward portion 5 curved upwardly and graduallyreduced in width and depth to a point at its front end. By so formingthe runners they will 4readily cut through the water as the boat isdriven forwardly, and the curvature of the forward portion 3 of thebottom 2 and front end portions of the runners will impart a lift to thebow of the boat as it moves orwardly. Cross bars Band 'l extend acrossthe under face of the bottom of the boat between front and rear endportions of the runners 4 and constitute end walls of a pocket 8 whichextends along the bottom of the boat and gradually increases `in widthltoward its rear end. The cross bars or iront and rear walls arelsubstantially V-shaped in cross section, as shown in Fig. 4, and froman inspection of this figure, it will `be seen that when the boat is inmotion, water and air may easily flow across these -end walls. It willalso be noted that since the pocket has end walls, air will beltrappedinthe pocket and air held therein` when the boat slows down and isbrought to a stop. The front wall B is deeper than the rear wall 1.

To force the boat through the water, there shown as helical bladesformed solid with their shafts, it is to be understood that they may bein the form of helical strips welded at their ends'` to the shafts, ormerely helical strips having stub shafts at their ends.

edges of the runners and the propellers project y,ed between therearwardly extending forks 22 of rudder posts 23. The rudder postsextend vertically and are rotatably mounted through sleeves i `2II Asecuredsto'and rising from the bottom 2 of The shafts ID are spacedupwardly a very short distance from the lower f I downwardly through theopenings I2 and out` wardly from opposite sides of the runners, as shownin Fig. 6, so that as the propellers are turned, their blades act uponthe water to drive the boat forwardly or rearwardly, according to thedirection in which the propellers are rotated. Universal joints I3connect forward ends of the propeller shafts with transmission shaftsyIll which extend forwardly at an upward incline and through the bottomof the boat, their front ends being connected to shafts of engines I5 byuniversal joints I6.

The specific type of engines used is optional, according to theconstruction of the boat. They maybe of the conventional fluid driveautomobile type with crank shafts located in the pontoons and connecteddirectly to the propellers, but in the illustration they have been shownlocated well forward of the boat and their exhaust pipes I'I extendrearwardly and terminate in enlarged mouths I8 secured about openings I9formed in the bottom of the boat. The exhaust pipes may havecommunication with air pocket 8 through the bottom of the hull, asshown, through sides of the pontoons, or in any desired manner. Air andexhaust gases passing from the engines and discharged into the airpocket 8 ow toward the stern of the boat and escape from the pocketacross the rear wall I thereof. Movement of air and exhaust gasesthrough the air pocket towardk the stern of the boat imparts a forwardthrust to the boat and serves t0 in-y crease forward speed of the boatas well as assuring a supply of air and exhaust gases in the pocket. Thepocket is thus filled with air and exhaust gases and this eliminatesdirect contact of the bottom of the boat and upper portions of sidewalls 0f the runners with the water. Therefore, frictional resistance isdecreased and the boat will be driven forwardly at high speed. As thespeed of the boat increases, uplift is imparted to the boat and thedraft is decreased from the normal draft level shown in Fig. 7, to thatof Fig. 8, and, referring to-Fig. 8, it will be seen that the onlyportion of the boat immersed in water are the lower portions of therunners. As the curved under surface 3 of the bow of the b oat movesforwardly, a certain amount of air moves rearwardly across the frontcross bar or wall `6 into the pocket 8, but the curved front face ofthis wall directs the water downwardly and imparts an uplift to the bowof the boat. The upwardly curved forward portions 5 of the runners alsohave a tendency to impart uplift to the bow as the boat moves forwardly.Guards 2U, formed of bars or strips of strong metal, extendlongitudinally of the runners under the openings I2 and the propellers9, with their end portions curved upwardly and welded to the lower edgeportions of the runners. These guards protect the propellers from damageby striking obstructions in the water and also permit the boat to theboat about yopenings formed therein, and upper ends of thev vpostsprotrude from the sleeves andfcarrytillers to which ends of the steeringline 26 are attached. The steering line extendsalong sides of the boatand is Wound about a drum 2.1 of the steering wheel 28 so that when thewheel is turnedthe tillers will be moved and the rudders adjusted tosteer the boat. The rod 29 causes the two rudders to be simultaneouslyadjusted. It will be understood that a single rudder may be 'used"insteadof double rudders, if desired. Since the rudders are rotatablysupported between the forks of the posts, they may turn about their'axles as the boat is driven through the water, thus reducing frictionalresistance of the rudders.

While it has been stated that the improved construction is particularlyadapted for speed boats, there is another eld for the invention in whichthe bottom air space is maintained continuously and used solely todecrease water drag and immersion of they boat. This field is typifiedby canal boats, ferries, landing barges, and the like, where heavyweights are to be carried, and also in instances where the water to betraveled is shallow. Itis evident that by substituting air for water asthe buoyant medium, the frictional drag is greatly reduced, permittinggreater speed with less power. Further, in many cases the twin screwpropulsion permits ready steering and maneuvering. The very shallowdraft permits use for landing and in waters where conventionalpropellers would be fouled.

In the case of canal boats, a. further advantage arises from the steadyslip stream of the helical propellers creating less damage to banks andbottom than the'turbulence of screwA propellers which prevent their usein some Waters. It is evident that utilizing the entire area of thebarge having only narrow runners at sides and streamlined cross membersfore and aft, a great percentage ofthe weight is air-borne. Also, instill waters, the depth of the air pocket need not beigreat', onlyenough to house small propellers so that moving parts are 'further fromthe bottom.`

To minimize frictionalfresistance, the center lines cf thefpontoons arearranged parallel to the axisv of the boat and the sides madesymmetrical to vthem so that there is a constant streamline motiontowardA the rear of the boat.

I am aware'that certain forms of sleds have been made in which' aboat'i's cut in two longitudinally and the two sections' transposed,leav ing a fiat outside and a curved inner section. It will be noted,however, that my invention differs in that the sides of the pontoons aresymmetrica] and the Vflow line of the water is par-y allel at all timesto the axis of the boat. This form of structure lends itself readily toquantity production since the boat bottom is essentially flat 'with therunnersI attached'thereto.

To'secure more eflicient propulsion, I propose that thepresentpropellers be of helical form and mounted to operate in thesection of the runners. 'I'his applies thrust directly in the line ofmotion instead of at an angle as is required with a propeller shaftslanting downward as in the conventional form of boat.

A still further advantage of this propeller is that it is working atmaximum efciency. Engineers recognize thatthe normal form of screwpropeller is a compromise one and that only one section works at maximumefficiency. At this point, the pitch is proportioned to the speed of theboat and there is very little slip. However, at points outside thisdiameter, it will be moving at higher velocity and at less emciencywhile points inside this pitch will be moving too slow for goodefciency.

By using a small diameter helical propeller, the thrust can beconcentrated along a very narrow area operated at maximum efficiency andan additional thrust obtained by the additional blades. Further, theturbulent effect of the improper proportions is minimized. With such apropeller mounted in the streamlined runner, the tendency of the wateris to flow smoothly along without turbulence.

The effect of the turbulence on ordinary speed boats can be seen byobserving the wake of the boat where the water is disturbed and thrownin all directions. A larger part of the energy is consumed in tossingthe water around rather than in propelling the boat forwardly. While theboat construction may be mounted on ordinary runners, I prefer the twintype propellers shown. These may be driven by two separate enginessynchronized, or with one engine with a driving gear.

Another field f usefulness for the invention is in the construction ofpontoons for airplanes. In this case, surface tension of still watergreatly retards take-oil and provision of the air pocket will not onlyprovide air buoyancy but the exhaust gases filling the pocket will breakup the surface tension and enable the airplane to rise more easily andwith less power.

Having thus described the invention, what is claimed is:

1. In a boat construction, a hull having pontoons extending along theunder face of its bottom at opposite sides thereof and constitutingbuoyant runners, and cross bars extending across the bottom of the hullbetween front and rear end portions of the runners and constituting endwalls for an air pocket having side walls formed by the runners, saidrunners being gradually reduced in width toward their rear ends wherebythe top of the air pocket gradually increases in width toward its rearend, and the front cross bar being of greater depth than the rear crossbar.

2. In a boat construction, a hull having pontoons extending along theunder face of the bottom thereof at opposite sides and constitutingbuoyant runners, and cross bars extending vacross the bottom of the hullbetween front and rear end portions of the runners and constituting endwalls for an air pocket having side walls formed by the runners, saidrunners being substantially V-shaped in cross section and graduallyreduced in width and depth toward their rear ends, and the front crossbar being of greater depth than the rear cross bar.

3. In a boat construction, a hull having ponl toons extending along theunder face of the bottom thereof at opposite sides and constitutingbuoyant members, and cross bars extending across the bottom of the hullbetween front and rear end portions of the runners and constituting endwalls for an air pocket having side walls formed by the runners, saidrunners being substantially V-shaped in cross section and graduallyreduced in width and depth toward their rear ends for substantiallytheir full length and each having an upwardly extending forward endportion tapered to a point at its front end, and the front cross barbeing of greater depth than the rear cross bar.

4. In a boat structure, a hull, hollow runners extending along thebottom of the hull at opposite sides thereof, cross bars extendingacross the under face of the bottom between front and rear end portionsof said runners and, together with the runners, forming an air pocketclosed along its sides and ends, said runners being substantiallyV-shaped in cross section and each formed substantially midway thelength of the hull with a longitudinally extending opening through itsside walls and lower edge, helical propellers rotatably mounted in saidrunners and extending longitudinally of the openings with their lowerportions protruding through the openings, port and starboard engines inthe forward portion of the hull, transmission shafts extendingrearwardly from the engines through the bottom of said hull and into thehollow runners and connected with front ends of the, propellers, andexhaust pipes for said engines extending rearwardly therefrom andthrough openings in the bottom of the hull for discharging exhaust gasesinto the forward portion of the air pocket in the direction of the rearend of the boat.

5. In a boat construction, a hull, hollow runners extending along thebottom of the hull at opposite sides thereof, cross bars extendingacross the under face of the bottom between front and rear end portionsof said runners and constituting end walls of an air pocket having sideWalls formed by the runners, said runners being substantially V-shapedin cross section and gradually reduced in width toward their rear endsand each formed substantially midway the length of the hull with alongitudinally extending opening through its side walls and lower edge,the front cross bar being of greater depth than the rear cross bar,helical propellers rotatably mounted in said runners and extendinglongitudinally of the openings, and transmission shafts extendingthrough the bottom of the hull and into the hollow runners and connectedwith said propellers.

6. In a boat construction, a hull, hollow runners extending along thebottom of the hull at opposite sides thereof, cross bars extendingacross the under face of the bottom between front and rear end portionsof said runners and constituting end Walls of an air pocket having sidewalls formed by the runners, said runners being substantially V-shapedin cross section and gradually reduced in width toward their rear ends,the front cross bar being of greater depth than the rear cross bar, anda power plant in the forward portion of said hull having exhaust meansextending rearwardly therefrom for discharging exhaust gases into theforward portion of the air pocket in the direction of the rear end ofthe boat.

CREEDY Cf. SHEPPARD.

